We have constructed a large fosmid library from a mesophilic anaerobic digester and explored its 16S rDNA diversity using a high-density filter DNA-DNA hybridization procedure. We identified a group of 16S rDNA sequences forming a new bacterial lineage named WWE3 (Waste Water of Evry 3). Only one sequence from the public databases shares a sequence identity above 80% with the WWE3 group which h...

Abstract Household biodigesters are self-mixing anaerobic digesters used mostly in rural areas of developing countries as a reliable source clean cooking energy. For an efficient digestion process, the mixing slurry inside digester is regarded one most important parameters. In this study, three different designs household digesters, namely fixed-dome (GGC 2047 model), plug-flow and prefabricate...

Eukaryotic communities in aerobic wastewater treatment processes are well characterized, but little is known about them in anaerobic processes. In this study, abundance, diversity and morphology of eukaryotes in anaerobic sludge digesters were investigated by quantitative real-time PCR (qPCR), 18S rRNA gene clone library construction and catalyzed reporter deposition-fluorescence in situ hybrid...

The nutrient-rich liquid stream produced during the dewatering of digested biomass (i.e., the centrate) is commonly mixed with the influent raw wastewater at wastewater treatment facilities. This increases the nitrogen and phosphorus loading on biological processes, increases operating costs, and in some cases, results in increased nutrient concentrations in the final effluent. Forward osmosis ...

Batch anaerobic digestion tests of primary sludge and waste activated sludge were conducted for a duration of 123 days to determine the ultimate degradability of the sludges. For primary sludges the inert fraction of the particulate COD that was predicted by the wastewater models could be employed to predict their biodegradability under anaerobic conditions. The degradation of waste activated s...

The influence of parameter changes on the bacterial community of a laboratory-scale anaerobic digester fed with glucose was investigated using a culture-independent approach based on single-strand conformation polymorphism (SSCP) analysis of total 16S rDNA and 16S rRNA amplification products. With the digester operating at steady state, the 16S rDNA SSCP patterns of the bacterial community show...

Wastewater containing high concentrations of salt, are difficult to treat using biological treatment processes, especially anaerobic processes. Limited information is available on methanogenic activity in saline environments. The objective of this research was to investigate the activity of halophilic methanogens, digester sludge and a mixed culture of halophilic and methanogenic bacteria, at v...

Anaerobic digestion is a common technology to biologically stabilize wasted solids produced in municipal wastewater treatment. Its efficiency is usually evaluated by calculating the reduction in volatile solids, which assumes no biomass growth associated with digestion. To determine whether this assumption is valid and further evaluate digestion efficiency, this study sampled 35 digester sludge...

BACKGROUND High levels of ammonia and the presence of sulphide have major impacts on microbial communities and are known to cause operating problems in anaerobic degradation of protein-rich material. Operating strategies that can improve process performance in such conditions have been reported. The microbiological impacts of these are not fully understood, but their determination could help id...

OBJECTIVE An experiment was conducted to isolate and identify new methanogens in Korea from an anaerobic digester that uses pig slurry. METHODS An anaerobic digestate sample was collected from an anaerobic digester using pig slurry. Pre-reduced media were used for the growth and isolation of methanogens. Growth temperature range, pH range, NaCl concentration range, substrate utilization, and ...